Refrigerating mechanism



Ocf- 13 1942 o. H. BuscHMANN. "2;293749 REFRIGERATING MECHANISM Filedoct. N25, 1940 ashun-sheet 1 l INVENTOR 0L 13, 1942 o. H. BuscHMANN2,298,749 REFRIGERATING MECHANISM Filed oct. 25, 1940 2 sheets-sheet 2INVENTOR ATToRN &

Patent'ed Uct. 13, 1942 REFRIGERATING MCHANISM Oskar H. Buschmann,Sidney, Ohio, assignor to Copeland Refrigeration Corporation, Sidney,Ohio, a. corporation o! Michigan i .Application October 25, 1940, SerialNo. 362,823

14 Claims.

This invention relates to refrigerating mecha` nism and particularly toa sealed motor compressor unit, the principal object lbeing theprovision of a device of the type described having certain new and novelfeatures of construction. Objects of the invention include the provisione of a novel lubricating mechanism for a sealed motor compressor unit;the provision of" novel means for maintaining the axial position of theshaft and rotor assembly of a motor compressor unit; the provision' of anovel construction for a pocket for collecting oil thrown about by thethrow, the motor shaft being hollow and a shoulvdered tube communicatingwith a pocket projecting into the interior of the shaft, a Washersubstantially iitting the tube being interposed between the shoulderonthe tube and the end of the shaft whereby to limit movement of theshaft in one direction, and spring means constantly urging the washeragainst the end of the shaft whereby to minimize the escape of oil fromthe interior of -the shaft about the exterior of the tube. v

vision of means for quieting the operation of a refrigerant or othercompressor; the provisin if of means in a refrigerating mechanism forminimizing the noise accompanying the discharge of means for use inarefrigerantcircuit; and the provisionof a mufiiing means for a gascircuit A subjected to intermittent impulses comprising a 4 coil ofclosely wound spring wire closed at one end and through which therefrigerant `must pass in flowing through the circuit, the turns in theOther objects of the invention include the prof coil separating underpressure to permit the gas 'to escape therethrough.

The above being among the objects of the present invention the same.consists in certain novel `features of. construction and combinationsof parts to be hereinafter described with reference to the accompanyingdrawings, and then claimed, having the above and other objects in view.

In the accompanying drawings which villus trate -a suitable embodimentof the present invention and in which like numerals refer to like" partsthroughout the several different views,

Fig. 1 is a more or less diagrammatic repre--V sentation of arefrigerant circuit embodying a sealed motor compressor unit;'

Fig.` 2 is an enlarged vertical sectional view taken axially .through asealed motor compressor yunitfor a refrigerating system embodying feartures of the present invention and taken as, for instance, on the line 22 of Fig. 1;

Fig. 3 is a fragmentary, transverse sectional view taken on the line 3-3of Fig. 2;

Fig. 4 is an enlarged fragmentary, sectional view taken inthe same planeas the view in Fig. 3 and illustrating the mechanism included in thecircle 4 of Fig. 3 in greater detail and in further partially brokenstate; and,

Fig. 5 is an enlarged fragmentary, sectional view taken in the sameplane as Fig.- 2 and illustrating those parts within the circle 5 ingreater detail.

The present invention has particular relation" to sealed motorcompressor units for refrigerating mechanism and is of the general typeof construction shown and claimed in` United States Patent` No.2,035,276, iiled by John R. Replogle and issued March 4, 1936, the samenow being owned by the assignee of the present invention. As is wellunderstood by those skilled in the art, in Vthis type of compressor allmoving parts of the motor and compressor are contained in a singlegas-tight housing eliminating the need of shaft seals or the like toprevent the escape oi' refrigeranttherefrom or the introduction of airthereto. In the Replogle patent above mentioned the motor and compressorhave a common shaft Awhich is hollow and through which the refrigerantis fed to the compressor end of the structure and lubricating oil is fedto the same end and Yis distributed therefrom to the various wearingsurfaces of the motor and compressor.

. In accordance with the present invention the i'eatureof feeding therefrigerant through the hollow drive shaft is eliminated but the hollowconformation of the shaft is retained and employed solely forlubricating purposes. In this case the shaft is not supported in thesame manner as in the Replogle patent and, therefore, requires avariation in the means for feeding the lubricant to the hollow interiorof the shaft. Because of the fact that there is no material flow ofrefrigerant through the shaft as in the Replogle patent and whicl flowof refrigerant in the Replogle patent serves to draw the lubricating oiltowards the compressor end ofthe shaft, means must be provided in thepresent construction for maintaining a body of oil in the hollow shaftand such construction forms one of the features of the presentinvention. Also in devices of this type it is preferable to allow thepower shaft a small latitude of freedom in an axial direction in orderto permit the rotor of the motor to seek its natural position axially ofthe stator, but, at the same time, means must be provided for limitingthe axial movement of the shaft so that in handling of the unit inshipping, service, or otherwise displacement of the shaft and the partscarried thereby will not be permitted to an undesirable degree. Inaccordance with the present invention the means provided for introducingoil into the interior of the hollow drive shaft affords a means wherebythe axial movement of the power shaft may be limited to the desireddegree.

Another feature of the invention which is applicable to compressorsgenerally but which is particularly adaptable for use in connection withrefrigerant compressors whether they be of the sealed type or not, is inconnection with muilling means for the discharge side of the compressor.As is appreciated by those skilled in the art the compressed refrigerantdischarged by the piston from the cylinder of a compressor into the highside of the system often sets up pulsations of a distinctly audiblenature and, because all parts of 'the refrigerating system andparticularly the refrigerant circulating passages are constructedentirely of metal, this pulsation noise is telegraphed through theentire system. Moreover on occasions a slug of oil V`willl be dischargedfrom the compressor and will be forced through the refrigerantcirculating system, and when such slug is carried through the system assuch distinctly audible sounds are created which are consideredundesirable. In accordance with the phase of the present invention underdiscussion means are provided whereby the pulsations of pressureoccurring at the outlet side of the compressor are smoothed out so thatthe refrigerant discharged into the circulation system is substantiallydevoid of pulsations, thus preventing the audible effects thereof frombeing telegraphed through the system and from being apparent therein. Atthe same time it serves to break up any slug of oil that attempts toflow through the system as such and thereby eliminates the undesirableeffects thereof.

Referring now to the accompanying drawings and particularly to Fig. 1there is diagrammatically illustrated a typical refrigerating system inwhich the numeral l0 indicates generally a motor compressor unit fromwhich refrigerant is discharged through a tube H to a condenser I2 inwhich the refrigerant is condensed and then delivered to a receiver VI4from which it is led through a tube I6 to an expansion valve i8 and thento an evaporator 20 in which the expanded gas absorbs heat and thenreturns through a tube 22 to the motor compressor unit I0 to again becompressed and re-circulated. The present .in-

venton particularly relates to the motor compressor unit l0.

Referring now particularly to Fig. 2 it will be noted that the motorcompressor unit I0 comprises a housing 30 the lefthandportion of whichis of generally circular section and the open end of which is closed andsealed in gas tight relation by means of a removable cover 32 secured inplace by screws 34. The opposite end of the housing may be formed toprovide one or more cylinders although in the present case by way ofillustration it is shown as formed to provide two cylinder bores 36therein. The righthand end of the housing is provided with an integralend wall provided with an axial bore 38 which is closed and'sealed by aplug 4U secured in place by screws 42 but which plug is provided with anaxial bore M in turn closed by a cap 46 secured in place by screws 46.The housing 38 is also provided with an opening below the cylinder bores36 which is closed and sealed by means of a cap 50 secured in place byscrews 52, this latter opening being for the purpose of facilitating theinsertion of the piston assemblies in the cylinders.

Intermediate the opposite ends of the ho sing 30 is a central integralwall 64 provided w n a central bore in which an elongated bearingbushing 56 -is ilxedly received. A shorter bearing bushing 58 is xedlyreceived within the inner end of the bore 44 of the plug 40. Rotatablyreceived by and between the bushings 56 and 58 is a power shaft 68having a bore 62. The righthand end of the shaft 60 is reduced indiameterV so as to form a shoulder 64 which axially abuts the inner endof the bushing 58 to thus limit movement of the shaft 60 to the right asviewed in Fig. 1. The bore 62 at the extreme righthand end of the shaft60 is reduced in diameter as indicated at 66 for a purpose which willhereinafter be more apparent.

Upon the shaft 60 and integrally therewith are two eccentrics 68 alignedwith respect to thecylinder bores 36. and encircling each of theeccentrics 68 is the big end of a connecting rod 16 the upper end ofeach of which ls connected by means of a piston pin l2 with a piston 14received in the corresponding bore 36. Accordingly, it will beappreciated that rotation of the shaft 66 causes reciprocation of thepistons 14, the ecceny trcs being displaced from one another angularlythrough 180 degrees so as to obtain alternate pumping strokes of thepistons 14.

The lefthand end of the housing 36 interiorly receives the stator of themotor, it preferably being pressed into position in a conventionalmanner which thereby xes it with respect to the housing 38. The rotor 82for the motor is pressed upon the corresponding end of the shaft 60 and,of course, is radially aligned with `the stator 80. Openings 84 and 86are provided in the central wall 54 so as to permit equalization ofpressures between the opposite ends of the housing 30 and additionallythe lower opening 86 provides for` the return of lubricating oil fromthe compressor end of the housing to the motor end thereof.

In order to provide lubrication for the various wearing surfaces of theunit lubricating oil is fed into tho bore 62 of the shaft 60 and it isdistributed therefrom to the various wearing surfaces. To aid ineffecting this result the shaft 82 is provided with al radial hole 88therethrough in line with the bearing bushing 5S and the shaft 60 isperipherally out away as at 90 on either side of the hole 88 to providean annular pocket for reception of the oil discharged thereinto from themoana bore 02 oi' the shaft160. Additionally the bore' of the bearingbushing 56 inline withthe hole 58 is internally provided withVanfannular `groove 82 to further aid in the flow of` oil `through theopening `08. It `willbe appreciated that during rotation of the shaft 60the oil in the shaft willbe subjected to centrifugal force which willtend to discharge `it radially outwardly through the yhole as well asother oil passages about to be described. In any event it will beyappreciated that the passage just .described affords a means whereby anample supply of oil may be fed to the wearing surfaces between the shaft00 and 'bear" ing bushing 60. .v l Another radial oil hole 04 isdrllledthrough the shaft centrally of each of the eccentrics 00 and onthe radially low side of suc-h'eccentrics.

Each connecting rod is provided with .a centrai. oil passage 08 which-is aligned with the corresponding oil passage 0l once duringi eachrevolution of the "shaft 60 so that oil discharged through the passagesl04 not only is fed to wearing surfaces between the connecting rods andtheir corresponding eccentrics G8, but is also fed through the passagessito the wearing` surface iting axial movement of theA shaft 00 to theleft. In order to accomplish this .result a `shoulder is formed onV thetube andwhile in 'the broader as- 1 `fpects of the present invention itmakes kno diference whether this shoulder is formed as an integral partof the tube or formed separately `thcrefrom, the. latter is illustratedas the preferable and `more economical manner of accomplishing thisresult. Accordingly, in order to provide such rshoulder a second tube||0 is sleeved-upon the tube |08 and the lefthand end thereof isarranged in abutting relationship with respect to the web |05. Theopposite end of the tube |1|0 s terminates short of `the correspondingend of the nut member |02, and particularly where a washer ashereinafter described in conjunction there with is not employed, will beof sulcient ydiameter to engage `the nut member |02 to limit movementthereof, and accordingly the shaft 00, to the left as viewed in thedrawings. Thus the a righthand end of the tube ||0 andthe lefthand Thesmall bore 66 i their cylinder bores 30 are lubricated by means of oilthrown oil? of the periphery'of the eccentrlcs 60 during operation.

In order `to introduce oil into the interior of the shaft 60 an oilthrower |00 is fixed to the' lefthand end of the shaft 60by means of ahoilow nut member |02 threaded into the corre-f spending end of the bore02. The radial extremities of the oil thrower |00 extend into ycloseproximityto the bottom side of the bore in the housing 30 at thecorresponding end of the housing 00 and sulcient lubricating oil isintroduced into the `systerrl so as to provide a pool of oil in thelower part oi the housing into which the ends oi the oil thrower dip.The ends of kthe oil thrower thus throw a spray of oil around theinterior housing and particularly against the inner circumferentialshoulder |04of the cover 32 and the cover 32 is provided on its innerside with a web |05 integral therewith and cooperat-y ing with the innerface of the cover to provide a central pocket |06 into which a portionof this oil drains by gravity. A tube |08 arranged in concentricrelation with respect to the shaft 60 has one end fixed in the web |05in open communicatian with the pocket |00 and the tube |00 extendsthrough the bore of the nutvmember |02 and into the hollow interior orbore 62 of the exaggerated for the purpose of illustrationxonly.`

This tuber|00 forming a means of communication between the pocket |06andthe bore 02 of the shaft 00 is, in accordance with the presentinvention, also employed as a means for limend of the bearing bushing 58will cooperate with the shaft 60 to maintain it agains't material axialmovement between them, a certain amount of` such axial movement beingpermitted so as to permit the rotorv82 to seekits natural centerwithinthey stator 80 as is conventionally de- 'Ihe nut member |02 having abore smaller than the bore 02 of' the shaft 60, its inner end serves inthe nature of a dam in the bore 62 serving to maintain a level of oil inthe bore 02. A greater level of oil in the bore 02 may tend to produceleakage of the lubricating oil from the bore S2 of the shaft 00 betweenthe bore of the nut |02 and the tube |08 unless otherwise prevented andthis particularly where a relatively free fit is provided between thesepartsl'A Such leakage may be prevented where considered `necessary ordesirable by means of a washer VH21," vwhich rotatably but relativelyclosely surrounds the tube |00 between the corresponding face of the nutmember |02 and the righthand end yjef the. tube H0, this washer ineffect cooperating 'y between the nut member and the tube ||0 to limitaxial movement of the shaft 670 to the left, and suitable axialclearance being left between the washer and the end of the tube ||0 forthe purposes previously described. A coil spring H4 surrounds the tube||0 and is maintained under turn with respect to the nut member |02during operation of the unit valthough it is `free to turn with respectto the spring H4; K

From the'Y above itwill be understood that in accordance with theconstruction thus far described means vare provided for introducing1ubricant into the hollow interior of the shaft 60 and distributingit'therefrom to the various wearing parts of the unit, the meansprovided for introducing the lubricant to the hollow in'- terior of theshaft also providing a means for limiting the axial movement of theshaft 60 in vone direction and further providing means whereby anunwarranted escape of lubricant from the lefthand endof the shaftis.prevented.`

terlorly'formed to provide a relatively large chamber |26'i`and receivedwithin the chamber |26 over each of the bores 36 is a valve plate |28provided with an inlet port |30 and a discharge port |32. A nat springtype valve |34 is arrangedand is provided with a pocket |42 therein in`open communication with the corresponding inlet port |30. As bestillustrated in Fig, 3 one side of the housingr 30 is provided with aninlet conj nectlon `member |42 of conventional construction to which thetube 22 of Fig. 1 or its equivalent is connected and through whichrefrigerant flows into a bore |44 in the casing 30. A wire screenstrainer |46 is provided in the bore |44 as illustrated in Fig. 3 notonly to entrap particles of foreign material carried by the refrigerantand preventing them from being carried to the interior of the motorcompressor unit, but also to separate out any oil from the refrigerantowing into the compressor. The bore |44 opens into a vertical bore |48which opens into the crankcase portion of the compressor end of thehousing 30 at its lower end and thereby affords a means whereby anylubricant separated out from the gaseous refrigerant in the strainer |46may flow by gravity into the lower part of the housing 30. The upper endoi' the passage |40 extends into open communicationv with the pocket |40of both members |38 so that upon each down stroke of each piston I4 thegaseous refrigerant will be drawn through the bore |44 and through thebore |48 to the corresponding pocket |40 and then down through thecorresponding suction passage |30 into the corresponding cylinder 36.'I'he `gas thus drawn into each cylinder 36 during the down stroke ofthe corresponding piston 14 therein is compressed upon the ensuingup-stroke of the piston and is caused to be discharged through thecorresponding discharge port 32 and through the corresponding passage|40 into the chamber |26 of the cylinder head |22. e

with respect to the walls of the bore |52 and the various coils of whichare tightly wound together when in normal condition. The lower coils arereduced in diameter as best illustrated in Fig. 4 and the coil at thelower end is closed by brazing or the like as indicated at |58. In orderto secure the coil |56 in position and in sealed rela'- tion withrespect to the walls of the bore |52,

the upper end of the bore |52 is outwardly flared as at |60 and theupper end of the coil |56 is outwardly flared as at |62, the dimensionsof these last two parts being such that when the cylinder head |22 isdrawn into place by the bolts |24 the flared portion |62 of the coil |56is firmly pressed into contact with the walls of the flared portion |60of the bore |52 and in substantially sealed relation with respectthereto.

It will be appreciated that because of the fact that the various turnsof the coil |56 are wound tight against each other, that except for theinevitable imperfections in the wire itself and in the winding thereofthe coil acts to block the flow Now referring again to Fig. 3 it will benoted that an outlet connection member |50 is provided on thatside ofthe housing 30 opposite the inlet connection member |42 and this memberis in communication with the chamber |26 of the cylinder head |22through a vertical passage |52 and horizontal passage |54, so that therefrigerant which is compressed and delivered into the chamber |26 mayflow out of the compressor through the outlet connection |50 and thenceto a condenser such as the condenser |2 illustrated in Fig. 1. It is inconnection with the discharge of compressed refrigerant from thecompressor that the remaining phase of the present invention isconcerned. In other words, means are previded in accordance with thepresent invention whereby the pulsations which are commonly set up bythe discharge of compressed refrigerant from the compressor are smoothedout and thereby muiiled and prevented from being telegraphed as audiblesounds throughout the entire system.

This means, as best illustrated in Figs. 3 and 4, comprises a coil |56of spring wire the major portion of which is arranged in spaced relationof refrigerant therethrough. However, the re' frigerant compressed bythe compressor in being delivered under a relatively high pressure tothe interior of the coil |56 causes the coil |56 to elongatesuiliciently to separate the various, or at least sufcient, turnsthereof to such an extent as to permit the escape of the refrigerantbetween them but, as will be appreciated, the coil delays the flow ofrefrigerant through it and requires a certain differentialof pressure onopposite sides thereof before it will separate sufficiently to permit amaterial flow of refrigerant through it. From a practical standpoint itis preferable to so construct the coil |56 that a pressure differentialof from one to live pounds will be suiiicient to separate the variouscoils thereof to an extent sufficient to permit the normal output of thecompressor to readily fiow therethrough,v and .although its presence maycreate a slightly greater head for the compressor to work in the amountis not sufficient to be material. Nevertheless, the resistance whichthe' oil collecting in the chamber |26 and attempting to flow throughthe passages |52 as a slug will be intercepted by the coil |56 and willbe broken up and mixed with refrigerant in flowing through it, thuseffectively eliminating the undesirable features which 'would otherwisebe apparent from the presence of such slug.

Formal changes may be made in the specific embodiment of the inventiondescribed without departing from the spirit or substance of thevassembly, a pumping element in said chamber operatively connected tosaid shaft for receiving driving movement therefrom, a motorincluding astator received within and xed with respect to said housing and a rotorfixed with respect to said shaft, means adjacent one end of said shaftassembly for limiting axial movement thereof in one direction, a pocketformed on the end wall of saidliousing adjacent the opposite end of saidshaft, means driven by said shaft for supplying lubricating oil to saidpocket, tubular means in open communication with said pocket andprojecting into the hollow interior of said shaft, and a shoulder onsaid tubular means arrangedlin cooperating relation with respect to saidopposite'end of said shaft assembly for limitsembly, a pumping elementin said chamber operatively connected to said shaft for receivingdriving movement therefrom, a motor including a stator received withinand fixed with respect to said housing and a rotor fixed with respect tosaid shaft, means adjacent one end of said shaft assembly for limitingaxial movement thereof in one direction, a pocket formed on the end wallof said housing adjacentthe opposite end of said shaft, means driven bysaid shaft for supplying lubricating oil to said pocket, and meansextending between said shaft assembly and said pocket providing for theflow of oil from said pocket to the hollow interior of said shaftassembly and cooperating with said shaftto limit axial movement of saidshaft in a direction opposite to the first mentioned direction of axialmovement.

3. In a sealed motor compressor unit, in combination, a housing havinga. pumping chamber formed integrally therewith at one end thereof. ahollow shaft rotatably 'mounted within said housing, said shaft having apassage therethrough leading to a wearing surface of said assembly, a

pumping element in said chamber operatively ing arranged to receivetherein oil acted upon by said oil slinger, a tube in open communicationwith said pocket extending into the bore of said threaded member, andshoulder means carried by said tube cooperable with said threadedmeinsaid shaft, means4 adjacent one end of said shaft for hunting axialmovement thereof in one direction, a hollow member threaded into thebore of said shaft at that end thereof opposite to the ber to limitaxial movement of said shaft inia first mentioned end and forming aninternal dam for retaining a body of oil in said shaft against escapefrom the corresponding end of said shaft, an oil slinger fixed to saidshaft by said threaded member, a pocket in `said housing arranged toreceive therein oil acted upon by said oil slinger, a. tube in opencommunication with said pocket extending into the bore of said threadedmember, and shoulder means carried by said tube cooperable with saidthreaded member to limit axial movement of said shaft in a directionopposite to the direction of the firstmentionedv axial movement.

5. In a sealed motor compressod unit, in combination, a housing having apumping chamber formed integrally therewith at one end thereof, i

assembly, a pumping element in said chamber operatively connected tosaid shaft for receiving driving movement therefrom, a motor including astator received within and fixed with respect to said housing and arotorfixed with respect to said shaft, means adjacent one end of said shaftfor Hunting axial movement thereof in one direction, a hollow memberthreaded into the bore of said shaft at that end thereof opposite to thefirst mentioned end, `an oil slinger fixed to said shaft by saidthreaded member, a pocket in said housing arranged to receive thereinoil acted upon by said oil slinger, and a tube in open communicationwith said pocket extending into the bore of said threaded member, saidtube having arelatively close running fit in said threaded memberwhereby to minimize the escape of oil from said shaft at thecorresponding end thereof between said tube `and said threaded member.

6. In a motor compressor unit, in combination, a hollow casing providinga cylinder therein, a

, hollow shaft assembly rotatably mounted in said casing, an eccentricon said shaft assembly, a piston in said cylinder operatively connectedto said eccentric, a pocket in said casing at one end thereof, means forsupplying oil to said pocket during operation of said unit. a tubeextending between said pocket and the interior of said shaft assemblywhereby to convey oil from said pocket to the interior of said shaftassembly, shoulder means associated with said tube cooperating with anend of said shaft assembly for hunting axial movement of said shaftassembly in one direction, means for limiting axial movement of saidshaft assembly in the opposite direction, said shaft assembly havingradially directed openings therein for .conveying oil from the interiorof said shaft assembly to wearing surfaces of said unit, and sealingmeans for the jointbetween said shaft assembly and said tube.

'7. In a motor compressor unit','in combination, a hollow casingproviding a cylinder therein, a

hollow shaft assembly rotatably mounted in said casing, an eccentric onsaid shaft assembly, a piston in said cylinder operatively connected tosaid eccentric, a pocket in said casing at one end thereof, means forsupplying oil to said pocket during operation of said unit, a tubeextending between said pocket and the interior of said shaft assemblywhereby to convey oil from said pocket to the interior of said shaftassembly, shoulder means associated with said tube cooperating with `oilfrom the interior of said an end of said shaft assembly for limitingaxial movement of said shaft assembly in one direction, means forlimiting axial movement of said shaft assembly in the oppositedirection, said shaft assembly having radially directed openings thereinfor conveying oil from the interior of said shaft assembly to wearingsurfaces of said unit, a washer closely but axially slidably received onsaid tube, and spring means constantly urging said washer against thecorresponding end of said shaft assembly whereby to seal the spacebetween said tube and said shaft assembly against undesirable leakage ofoil therebetween.

8. In a motor compressor unit, in combination, a hollow casing providinga cylinder therein, a hollow shaft assembly rotatably mounted in saidcasing, an eccentric on said shaft assembly, a piston in said cylinderoperatively connected to said eccentric, a pocket in said casing at oneend f thereof, means for supplying oil to said pocket during operationof said unit, a tube extending lbetween said pocket and the interior ofsaid shaft assembly whereby to convey oil from said pocket to theinterior of said shaft assembly, a washer surrounding said tube inabutting relationship with respect to said shaft assembly, a second tubesurro'unding the first mentioned tube and terminating short of saidwasher whereby to cooperate with said washer in limiting axial movementof said shaft assembly in one direction, means cooperating with saidshaft assembly to limit axial movement thereof in the oppositedirection, and said shaft assembly havingradially directed oil passagestherein for conveying shaft assembly to wearing surfaces of said unit.

9. In a refrigerant compressor, a cylinder block having a at head endand a refrigerant discharge passage opening on to said end, a cylinderhead overlying said end and having a chamber therein opening onto saidpassage, that end of said passage opening onto said end being radiallyenlarged to form a seat, a hollow coil of wirewound with the turnsthereof in substantial contact with each other positioned in saidpassage in generally spaced relation with respect to the walls thereof,one end of said coil being enlarged in diameter and being received insaid seat and clamped therein by said cylinder head, and the oppositeend of said coil being closed, said coil being formed of spring-likematerial whereby when the interior thereof is subjected to the dischargepressure of said compressor the turns thereof will separate axially fromone another to permit the flow of refrigerant therethrough.

10. In a gas compressor of the type wherein a piston reciprocates in acylinder and the cylinder is provided with a discharge passage having anassociated valve permitting flow of gas from said cylinder therethroughonly in a direction from said cylinder, the combination with saidpassage of means arranged in obstructing relation therein on thedownstream side of said passage from said valve, said means beingAlocated at a sufficient distance from said valve as to provide apulsation chamber of material volume in the uid passage between it andsaid valve, and said means comprising a hollow coil of ilexible wirewound with the coils thereof normally substantially in contact with oneanother and having one end thereof closed and the opposite end thereofsealed to the walls of said passage,

said means being arranged to receive the iiowy of gas from saidcompressor in the hollow interior thereof.

1l. In a gas compressor of the t'ype wherein a piston reciprocates in acylinder and the cylinder is provided with a discharge passage having anassociated valve permitting dow nf gas from said cylinder therethroughonly in a direction from said cylinder, the combination with saidpassage of means arranged in obstructing relation there-I in on thedownstream side of said passage from said valve, said means beinglocated at a suiiicient distance from said valve as to provide apulsation chamber of material volume in the fluid passage between it andsaid valve, and said means comprising a hollow coil of flexible wirearranged with its major portion in spaced relation with respect to thewalls of said passage and the various turns thereof normally insubstantial contact with one another, one end of said `coil being closedand the opposite end of` said coil being sealed to the walls of saidpassage, the latter endv of said coil being disposed on the upstreamside of the normal flow in said passage with respect to the closedendthereof.

l2. In a gas compressor of the type wherein a piston reciprocates in acylinder and the cylinder is provided with a discharge passage having anassociated valve permitting flow of gas from said cylinder therethroughonlyv in a direction from said cylinder, the combination with saidpassage of means arranged in obstructing relation therein on thedownstream side of said passage from said valve, said means beinglocated at a sufficient distance from said valve as to provide apulsation chamber of material volume in the fluid passage between it andsaid valve, and said means comprising a hollow coil of wire arrangedwith its majo;- portion in spaced relation with 'respect to the walls ofsaid passage and the varito the closed end thereof, said wire being of aspring-like character and at least part of the turns thereof beingadapted to separate from each other on the application of pressureinternally of said coil whereby to permit the flow of gas therethrough.h

13. In a gas compressor of the type wherein a piston reciprocates in acylinder and the cylinder is provided with a discharge port having anassociated jvalve permitting flow of gas from said cylinder therethroughin one direction only, the combination with said discharge port of apair of associatedmembers arranged to receive said gas discharged fromsaid port past said valve, one of said members having a passage thereinfor the iiow of said refrigerant and said passage being enlarged toprovide a seat adjacent the line of junction of said members, a hollowcoil of Wire having the turns thereof in sub` stantial contact with eachother received within said passage, said coil being provided with aradial enlargement adjacent one end thereof received in said seat andclamped thereagainst by the other of said members when said members aresecured together, the opposite end of said coil being closed, and saidWire being of resilient characteristics whereby pressure on the interiorof said coil materially in excess of that on the exterior thereof willeffect elongation of said coil and separation of at least certain turnsthereof to permit the ow of refrigerant therethrough.

14. In a gas compressor of the type wherein,

a piston reciprocates in a cylinder and the cylinder is provided with adischarge port having an gas discharged from said port past said valve,one l0' of said members being provided with a passage therein and theother oi said members overlying a face of the tlrst mentioned member andarranged to deliver refrigerant to said passage, said passage beingoutwardly iiared at that end 15 thereof closest to the second mentionedmember,y and a hollow coil of resilient wire disposed in said passage ingenerally spaced relation with respect to the walls thereof, said coilbeing wound with the various turns thereof in substantial contact withveach other and the turns at one end thereof being enlarged to form atapered end portion complementary in shape and size to said flaredl endAof said passage and received therein, said tapered end being clampedagainst the walls of said ilaredy end of said passage when said secondmentioned member is secured to: said rst mentioned member, and theopposite end of said coil being closed.

OSKAR H. BUSCHMANN.

